Gamma World* is a great option for a lite Fourth Edition Game, and its a complete game unlike the Red Box or Essentials Book. The players have less powers to worry over and the optimizing is done for them. Some dislike the wacky Post Apocalyptic setting, but the boxed game can be re-skinned into any format. Below are just a few.

Dungeon World: Converting the game to fantasy is easy. Most character origins roughly correspond to a race or class available in D&D 4e or a monster race not usually allowed to PCs. Robotic Origins only mean the PC is half golem, crystaline, living statue, or rock elemental. Origin powers are martial arts, psychic abilities, orisons, or spells. Alpha Mutations come from magic potions the group finds. Omega Tech is magic items discovered while adventuring. Also check out the "Dungeon World" origins listed below.

Gamma Space: Movies like Star Wars* and Star Trek* have an infinite variety of alien lifeforms. The pulp comics of Flash Gordon, Buck Rogers, and John Carter of Mars can use the Gamma World* rule set unchanged except for favor and location. For a game of human technocracy collapse like Fallout*, Darksiders*, Borderlands*, Bioshock*, or Dead Space*, I suggest that every character start as an Engineered Human and only one randomly rolled origin. Omega Tech remains an unchanged mixture of science and alien artifacts. Alpha Mutations can be disallowed for realism or are the product of DNA manipulation, nanobots, or robotic gadgetry. The creatures of Gamma World make deadly aliens, killer robots, and excellent deep space zombies. Inspiration for Gamma Space adventures can come from any science fiction movie, video game, book, or TV show.

Steam World: Oddly for a game about the Post Apocalypse, with a little tailoring Gamma World* can be the rule set for Victorian Era Adventuring. Consider Call of Cthulhu, 20000 Leagues Under the Sea, The Island of Dr. Moreau, Sinbad the Sailor, War of the Worlds, Tarzan, Dracula, Frankenstein, The Wolf Man, or The Lost Continent. Any of these literary classics can be the basis of an adventure of exploration and discovery of creatures and artifacts unknown to the rest of the world.

Gamma Power: Comic books have claimed for years that radiation will give you superpowers. You can use Gamma World* rules to create your own superhero. Rolling up an origin decides what superpowers you have and how odd you look. In this variation, I would suggest players chose in advance a private stack of seven Alpha Mutation Cards, no more than two alike, that represent unique power stunts the hero can cycle through during an adventure.

Lightfoot Halfling

His deft hands and sprightly footwork leave you flatfooted

LIGHTFOOT HALFLING TRAITS

Ability Score: DEXTERITYSkill Bonus (Level 1): Gain a +4 bonus to Athletics checks.Nimble Feet (Level 1): Gain a +2 bonus to Reflex and a +2 bonus to AC vs. Opportunity Attacks.Lucky Dodge (Level 1): Once per encounter, you can force an opponent to re-roll a successful attack.Small Size (Level 1): You gain a +1 attack bonus and a +1 AC bonus due to your size ,but you can not use two handed weapons.Lightfoot Critical (Level 2 or 6): When you score a critical hit, the attack deals 1d10 extra damage, and you can shift one square after the attack.

WOOD ELF

You have superb coordination, are always aware of your surroundings, and hate being called a tree-hugger, because the true insults always hurt the most.

WOOD ELF TRAITS

Ability Score: DexteritySkill Bonus (Level 1): Gain a +4 bonus to Stealth checks.Quick on Your Toes (Level 1): Gain a +2 bonus to Reflex.Keen Eyes (Level 1): When your target has cover, you only take a -1 penalty to the attack roll instead of -2.Fleet (level 1): Gain a +1 bonus to speed.Elf Critical (Level 2 or 6): When you score a critical hit, the attack deals 1d10 extra damage, and you can shift 3 squares as a free action.

Mountain Dwarf

You can't be moved...unless there are precious metals involved.

MOUNTAIN DWARF TRAITS

Ability Score: ConstitutionSkill Bonus (Level 1): Gain a +4 bonus to Nature checks.Child of Stone (Level 1): Gain a +2 bonus to Fortitude and a +1 bonus to AC.Encumbered Speed (Level 1): You move your speed, even while wearing heavy armor or carrying a heavy load.Stocky (Level 1): Take a -1 penalty to speed.Dwarf Critical (Level 2 or 6): When you score a critical hit, the attack deals 1d10 extra damage, and you gain a +4 bonus to AC until the end of your next turn.

STAND YOUR GROUND - MOUNTAIN DWARF UTILITYYou've chosen this spot to stand, and stand there you shall.EncounterImmediate Interrupt - PersonalTrigger: You are hit by an attack that pulls you, pushes you, slides you, or knocks you proneEffect: You aren't pulled, pushed, slid, or knocked prone by the attack.

GROUND AND POUND - MOUNTAIN DWARF EXPERT

You knock your foe to the ground and smash'm.

Encounter * Physical, Weapon

Standard Action - Melee weapon

Target: One Creature

Attack: Constitution + your level + weapon accuracy vs. Reflex

Effect: You foe is knocked prone and you can make an immediate basic attack on the target and add your Constitution modifier to the damage inflicted.

OrcHealthy Green Blooded WarriorYou possess an endless depth of rage and love of violence. Everyone should see you are far superior to any weak, pink skinned, human and you don't mind knocking skulls together to prove it.Appearance: You have green skin, long arms, a pair of tusks jutting from your lower jaw, and beady yellow eyes. You may use any armor, tool, or weapon available to other humanoids. The exact nature of your dress and occupation depends on your secondary origin roll.

War Cry Orc UtilityYou bellow and beat your shield displaying to one and all your superior resolve and furyEncounteraBioImmediate Reaction PersonalTrigger: You fail a saving throw to end an ongoing effectEffect: You re-roll your save adding a +5 power bonus to the roll. If successful, you gain 5 plus your level temporary hit points.

From The Earth We Come, And In The Earth We Remain You know that worms are clever, subtle, and graceful and have no need of limbs or a ridged skeleton. You can see, hear, talk, and hold objects by coiling your lower body around them.

Appearance: You are a limbless, sticky, flesh-hose and those are your good qualities. The worm covers not only invertebrates, but non-venomous snakes, slugs, tape worms, leeches, eels, and limbless lizards.

Worm TraitsMutant Type: Wisdom; Bio; +2 to bio overcharge Skill Bonus (Level 1): Gain a plus +4 bonus to StealthPerseverance of the Downtrodden (Level 1): +2 to Fortitude Writhe and Wriggle (Level 1): You are hard to pin down and have a +2 to defense bonus against attacks that would result in you being knocked prone, immobilized, or restrained.Worm Critical (Level 2 or 6): When you score a Critical Hit, the attack deals 1d10 extra damage. If it is a melee attack, can move as a free action to any square adjacent to your target.

Worm PowersCreepy Crawler Worm NoviceYou are able to move through a crowd of enemies to reach your true target.EncounteraBio, PhysicalStandard Action Melee weaponTarget: 1 creaturesAttack: Wisdom + your level + Weapon Proficiency vs. ACEffect: You shift a number of squares equal to your Wisdom Modifier even if they are occupied by others without provoking opportunity attacks before or after you attack.Hit: 1[W] + Wisdom Modifier + your levelPlumbing Snake Worm UtilityYou can squeeze through a narrow pipe, mouse hole, or burrow just below the surface of the soilAt WillaBio, PhysicalFree Action PersonalEffect: You can move normally through the top layer of loose dirt or sand, a narrow duct, or a pipe that only a "Tiny" creature could fit through. This utility is especially useful for sneaking up on a target. You can't wear armor or hold objects while squeezing or burrowing. A successful "Stealth" check means you remain undetected (unheared and unseen).Strangle Hold Worm ExpertYou use your body to bind your foe while you slit its throatEncounteraBio, PhysicalStandard Action Melee weaponTarget: 1 creaturesAttack: Wisdom Modifier + your level + W.P. vs. ReflexHit: 1[W] + Wisdom Modifier + your level weapon damage and your target is "restrained" until your next turn.Sustained Attack: You can repeat this power each round on your target by spending a standard action and succeeding at another attack roll vs. reflex (as above). While holding your foe restrained you occupy the same square, you provide it partial cover with your own body, are hit by any area effects that hit your target, and grant combat advantage to any other creatures that wish to attack you. If you stop sustaining your attack or fail an attack roll your "strangle hold" is broken.